[meteorite-list] Three Martian Meteorites Triple Evidence for Mars Life

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Sun, 10 Jan 2010 18:16:07 -0800 (PST)
Message-ID: <201001110216.o0B2G7b7003395_at_zagami.jpl.nasa.gov>

http://www.spaceflightnow.com/news/n1001/09marslife/

Three Martian meteorites triple evidence for Mars life
BY CRAIG COVAULT
SPACEFLIGHT NOW
January 9, 2010

The team that found evidence of Martian life in a meteorite that landed
in Antarctica believes that during 2010, by using advanced
instrumentation on now three Martian meteorites, it will be able to
definitively prove whether such features are truly fossils of alien life
on the Red Planet.

This new information goes well beyond the updated findings released by
NASA in November 2009 about signatures for magnetic type bacteria.

"We do not yet believe that we have rigorously proven there is [or was ]
life on Mars." says David S. McKay, chief of astrobiology at the NASA
Johnson Space Center.

"But we do believe that we are very, very close to proving there is or
has been life there," McKay tells Spaceflight Now.

"The possibility of life on Mars has become a scientific issue of
profound importance and great public interest," Michael Meyer, the NASA
Headquarters senior scientist for Mars exploration, told an audience of
several hundred scientists at the recent American Geophysical Union
meeting in San Francisco.

And in a 2009 editorial, The Economist, a highly regarded British
publication, also noted the explosion of both public and scientific
interest in Mars saying "the possibility of life on Mars is too
thrilling for mankind to ignore."

In the mid-1990s, when the JSC team found what it interprets as Martian
fossils inside a meteorite that landed near Allen Hills in Antarctica,
it was the only example at the time of suspected fossils in a meteorite
from Mars.

The team, however, believes it has since tripled its fossil-like data by
finding more "biomorphs" (suspected Martian fossils) inside two
additional Martian meteorites, as well as more evidence at other spots
in the Allen Hills meteorite itself.

Remarkably, some of the most striking new evidence for life on Mars is
being found inside in a meteorite that has been sitting in the British
Museum of Natural History in London for nearly 100 years, says McKay.

Had British researchers examined their "Nakhla" meteorite with readily
available electron microscopes and other tools like those used by the
U.S. team, the new evidence for life on Mars could have been a British
discovery, rather than an American one.

The Houston-based scientists believe the age spread of their data, from
3.6 billion to 1.4 billion years ago, shows that a planet-wide network
of micro-organisms came to life underground on Mars 3.6 billion years
ago during the first billion years after Mars had formed along with the
rest of the planets in the solar system.

Mars was much warmer and wetter with a much thicker atmosphere then.
Simple life forms were beginning to form on Earth at about the same time.

Scientists are able to tell that the meteorites came from Mars by
measuring the noble gases trapped in the rocks and also by their
geologic character. The noble gas ratios measured to determine Martian
origin are helium, neon, argon, krypton, xenon and radon.

The twin Viking landers of the mid-1970s measured Martian surface gas
compositions in great detail, and the now more than 80 meteorites have
been found and designated as being from Mars.

They all have internal gas compositions that match the Viking lander
data, as well as Mars rock compositions measured by spacecraft at the
planet.

"Similar biological type findings in three different meteorites that
also correlate well with ancient Earth organisms considerably broaden
the evidence for at least past life on Mars," says geologist Everett K.
Gibson, co-leader with McKay and Kathie Thomas-Keprta on the JSC Mars
life study team.

According to the JSC team, the three Martian meteorites with the
apparent fossil signatures include what appear to be mats of bacteria
and specific other biological signatures that are common to all three
meteorites.

They are also highly similar to undisputed micro-fossil life of ancient
organisms found in Earth's rocks like Columbia river basalts in
Washington state.

In its November update, the Mars team said that for more than a decade
after the Martian meteorite data were first presented in 1996, opponents
of the life theory argued that fossil-shaped features and associated
chemical purity was just as likely caused by the thermal/shock event
that blasted the material off Mars in the first place.

But new research led by Thomas-Keprta of the Allen Hills team in Houston
has now proven the thermal theory is invalid. She says that finding
strengthens the team's argument that uniquely-shaped "magnetic bacteria"
features found in the meteorite were indeed formed by biologic activity
on Mars and not some non-biologic thermal event.

The new information from the team here goes well beyond the magnetic
bacteria that dominated the NASA November release. McKay and co-leader
of the Mars life team, JSC geologist Everett K. Gibson, have since
provided Spaceflight Now with much more detail on two other major areas
that will be the focus of more verification work starting this year.

Noted astronomer the late Carl Sagan often said "extraordinary claims
require extraordinary evidence," and the Johnson Space Center Mars life
team believe they now have, or by year's end will have, such evidence.

The two new areas involve:

o More advanced instruments: Powerful analysis hardware that was
unavailable or less capable when the Mars meteorite life analysis began
in 1994 is about to be used on the samples in all three meteorites. This
includes more capable High Resolution Electron Microscopy tools and a
major new tool -- an Ion Microprobe analysis system.

The Microprobe system will fire a focused stream of ions onto the
biomorph/micro-fossil samples. The ions will flash the sample into
plasma containing multiple constituents. A powerful spectrometer will
then suck that in and out the other side read out constituents of each
sample down to parts per billion level for each chemical or mineral
constituent. Those ratios will then be used to determine whether the
feature has its origin in non-living Martian geology or something
biologic that was previously life on Mars.

The new ion microprobe system should also provide the team with even
higher optical resolution than the electron microscopes they have been
using while also adding a major new chemical analysis dimension, says
McKay.

o Triple the meteorite samples: The JSC team is finding more micro-fossil
evidence of life in the Allen Hills meteorite discovered in 1984 that in
1996 provided initial evidence of Martian life.

The team calculates that the Allen Hills meteorite is made of
4-billion-year-old Martian rock carrying fossil evidence of life dating
back to 3.6 billion years.

This is an extremely old sample not comparable to anything on Earth
today because all of Earth's crust has been processed and reprocessed as
part of Earth's plate tectonics. The sample is already proving the
presence of water on Mars back to its early days as a planet. If the
fossil evidence is confirmed, it will prove that organisms existed on
the planet within about 1 billion years of its formation.

After the initial Allen Hills announcement made in 1996 with President
Bill Clinton, the Houston team began to search for similar life examples
in other meteorites from Mars. And they found that evidence in the
already famous Nakhla meteorite that fell near the town of Nakhla,
Egypt, in 1911. Nakhla fell in about 40 pieces weighing about 20 lb. total.

The largest sample set from that meteorite has been in the British
Natural History Museum in London and virtually all of several pieces of
Nakhla, which put on a spectacular show of flaming debris, smoke trails
and sonic booms when it arrived at about 9 a.m. local time in the Nakhla
region of Egypt south of Cairo.

A local farmer claimed that one piece struck and killed a dog. But
scientists believe the story was dreamed up by the land owner at the
time seeking to boost prices for buyers seeking to purchase pieces.

Then in 2000 a Japanese search team found another meteorite from Mars in
Antarctica. It is designated Yamato 593 and also contains signs of
fossil life similar to that seen in the Allen Hills and Nakhla
meteorites. Both the Nakhla and Yamato life forms date to only about 1.4
billion years old, if it can be proved more definitively.

The new evidence for life on Mars is being substantially increased by
the discovery of such potential Martian fossils in additional meteorites
beyond the original meteorite discovered in 1984 at Allen Hills
Antarctica, says McKay.

Answering whether life, even single-celled organisms, formed on another
planet is one of the most profound questions in modern science,
especially if the answer is positive.

If that can be verified soon, it will also play a major role in Mars
space mission operational decisions and the formation of new exploration
policy by NASA and the White House. Examples are:

o More focused Mars life strategy: NASA's original strategy was to "follow
the water" then shift to a strategy of "follow the carbon." The strategy
now, however, has been changed again and the new motto pulls no punches.
It now simply reads "find direct evidence for seeking out life," says
Meyer. That role will first fall to the Mars Science Laboratory rover
undergoing final assembly for launch in September 2011.

o Next rover site selection: The Mars Science Laboratory (MSL) rover,
named Curiosity and planned for launch in September 2011, will be
specifically targeted for landing at a carbonate-rich site. It will be
equipped to specifically look for Martian life as well as habitable
areas for Martian organisms. MSL will be NASA's first dedicated
astrobiology mission to Mars since the two Viking landers in 1976. Data
from the meteorites will be very important in the analysis of MSL
life-related findings, Gibson says.

o Life's role in the solar system: If the meteorites' biomorphs prove to
be true fossils of Martian life, the data will play a huge role in the
assessments for life elsewhere in the solar system, such as in the
ice-covered oceans of Jupiter's moon Europa. NASA plans to launch in
2020 a major new outer planets spacecraft -- the new Europa Jupiter
System Mission -- to orbit Europa and assess the potential for life there.

o Life's role in the Milky Way: Positive life determinations from the
three meteorites would play a role in the assessment of life on
Earth-like planets in the galaxy being sought out by the new Kepler
observatory spacecraft that has already discovered five Jupiter-size
planets in orbit around distant stars.

o Broader study of carbonates: McKay says that all three of the meteorites
contain substantial carbonate rock where the apparent fossils are
located. Neither rover on the Martian surface has been able to study
carbonate rock. If Opportunity can last another year, it will reach
Endeavour crater, where such high priority carbonate rock is assessable.

o Rover Opportunity drive strategy: The Mars Reconnaissance Orbiter (MRO)
spacecraft has found clay-bearing rocks lying directly in the path ahead
for the Mars rover Opportunity. It will reach its 6th anniversary on
Mars on January 24th and is driving dozens of feet each day toward
Endeavour crater that is surrounded by carbonate-rich rock types like
that holding fossils in the meteorites. If it can survive another year
to drive the final 7-8 mi. to Endeavour crater, the rover will be able
to image and analyze this totally new rock type never visited by a rover
before. As a carbonate like that in the meteorites, the area ahead of
Oppy could have provided a wet, warm, and non-acidic habitat for the
formation of life on Mars, Steve Squyres, rover principal investigator,
tells Spaceflight Now.

"Even though we do not think the Endeavour crater is where these
meteorites came from on Mars, any information that Opportunity could
provide on the layering of similar carbonate rocks would be very useful
to us," said Gibson.

The other rover, Spirit, marked its 6th anniversary on Jan. 4, but NASA
is resigned to declaring Spirit's roving days are over where it has been
stuck since April in water and volcanically altered soils near the
equator on the opposite side of Mars from Opportunity. Given Spirit is
stuck for good, the science team is now preparing a detailed stationary
spacecraft science program for Spirit but may try and run and steer its
stuck wheels even deeper to tilt its solar array deck more toward the
sun so the spacecraft can survive at least one more winter on Mars.

Analysis of the Allen Hills, Nakhla and Yamato meteorites show the rock
was blasted from depths as shallow as one-half mile and as deep as four
miles. This puts them directly in the subsurface water table of Mars,
Gibson said.

Maria Zuber, who heads MIT's Department of Earth, Atmospheric and
Planetary Science addressed the latest Mars water data this week at the
American Astronomical Society meeting in Washington, D.C.

"Recent observations of Mars from orbiting and landed spacecraft have
dramatically changed our understanding of the distribution and amount of
water at and beneath the surface throughout the planet's history," says
Zuber.

"There is definitive evidence for a watery past, including standing
water on the surface, during Mars' early history, and the details of the
global hydrological cycle, groundwater upwelling and aqueous chemistry
have been elucidated.

"There is evidence that much past surface water is currently stored in
the upper crust in the planet's impact-generated regolith," she says.
"And present-day Mars contains abundant water ice within a meter of the
surface," says Zuber.

The "biomorph" features discovered in the Yamato 593 meteorite look
identical to those found inside the Allen Hills and Nakhla meteorites
says McKay.

Those Martian samples are also contained along with a mineral substrate
called Iddingsite. In such material, the presence of carbonate is a
giveaway for what on Mars would have been an underground aquifer with
substantial water to generate this type of sample, McKay tells
Spaceflight Now.

The Iddingsite deposits continue to form and change the longer water
flows through the rock providing additional evidence about the life
forms that create tiny biomorphs -- the early stage for fossils that are
most abundant with Iddingsite.

Not only is there now abundant evidence for underground Mars life, the
Japanese Yamato and Egyptian Nakhla samples, as well as increased
samples of apparent fossils, look identical to samples in the Allen
Hills meteorite.

"Every biologist that I have shown these new Nakhlite and Yamato
pictures to agree that they are microbial remains and fossils," McKay says.

And all of them look very similar or identical to the Earth fossil life
examples found in Columbia River basalts in Washington State.

The Martian samples have been recovered from Martian depths ranging from
an estimated one-half mile below the surface to as much as about 4 miles
deep.

Allen Hills team members tell Spaceflight Now that this is especially
fortuitous because many assessments about where Mars life would most
likely survive is underground, out of reach from solar radiation and
where aquifers most likely exist to hold life-giving water.

This is also because those depths match assessments on where the
underground Martian water table would have been the most active. Many
Mars Reconnaissance Orbiter and Mars Global Surveyor images show what
appear to be discharges of water from canyon and crater walls.

That data was summarized initially before the Society of Photo-Optical
Instrumentation Engineers.

NASA rolled out the findings again in greater depth before the American
Geophysical Union Meeting last week in San Francisco. That meeting was
attended by 16,000 international scientists and managers who work in the
field of geology, geophysics and other exploration related fields.

Some of the data described here was prepared by McKay initially for
presentation to the Society of Photo-Optical Instrumentation Engineers.

"The biomorphs in these last two meteorites are nearly identical,
supporting our hypothesis that they formed on Mars," McKay told
Spaceflight Now.

He also noted that the similarity of the biomorph features across the
three main Mars meteorite samples also argues against contamination by
material that instead may have formed on Earth.

And Nakhla also scores big when it comes to "following the carbon."

"We see considerable carbon in Nakhla," says McKay.

He cited the work of University of Arizona geoscientist Dr. A.J. Timothy
Jull, who has shown that at least 70 percent of the carbon in Nakhla is
not from Earth but had to come from Mars.

The new Martian life evidence has come to light just as President Barack
Obama is examining increased funding for NASA.

That federal budget decision is being made in the wake of presidential
review commission findings that the agency needs at least $3 billion
more annually to develop new launchers and spacecraft that would both
replace the space shuttle and send astronauts beyond Earth orbit with
Mars the ultimate destination before mid-century.

That Mars is the ultimate destination is pretty clear in the report by a
team headed by Norm Augustine, former CEO of Lockheed Martin. But how to
go about it remains the bigger unanswered question.

Independent researchers in New Mexico and Hawaii say images and
geochemical data from MRO and the European Space Agency Mars Express
orbiter indicate that the Allen Hills meteorite was blasted out of the
southern end of the vast Valles Marineris in a canyon at a junction
called Eos Chasma.

In a striking coincidence, this location believed the source for the
first meteorite found to carry evidence of Mars life to Earth is fed
directly by a channel named after the late "Orson Welles."

In 1938 he panicked the entire U.S. with his Halloween radio news
bulletin broadcast of H.G. Wells fiction "War of the Worlds" about the
first Martian landing in New Jersey.

This is the second of a pair of articles updating the analysis of
evidence for life on Mars carried to Earth in meteorites. The first
appeared in Spaceflight Now on Nov. 24, 2009.
Received on Sun 10 Jan 2010 09:16:07 PM PST